Welcome Despoiler
I'm not even going to go where a 1000 is required over 500
.......but it would be nice to know
But we'll have a crack at it regardless
Have you tried several different ports ? ....... Update USB2 driver ? ....... Re-install USB2 drivers to rule out corrupt drivers ?.......
disable USB mass storage in BIOS ....... try the mouse in another machine with the 1000 SPS (samples per second) setting.
Aussie Allan